Loki Patera, Io's Super-Hot Lava Lake
Loki Patera is the biggest volcanic depression on Io, and is shaped somewhat like a horseshoe. Its lava lake is consists of molten lava covered by a periodically overturning crust. The lake has been continuously active since at least 1979, when Voyager 1 conducted its flyby of Jupiter. Io has an estimated 400 active volcanoes on its surface, which cracks and flexes due to the gravity of Jupiter and Europa.
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Key Facts In This Video
Io orbits Jupiter faster than its outer sister moons, Europa and Ganymede. (0:36)
The largest volcanic eruptions in the solar system occur on Io. (2:52)
Io's volcanic plumes can reach 500 km (310 mi) above its surface. (3:24)